CNN host David Axelrod started the discussion by noting that there has been speculation that Arizona, a state McCain represented, could turn blue come 2020.
"Is that a real possibility?" he asked.
"I think it is," McCain replied.
She explained that Demographic changes in Arizona have changed the electorate, arguing that young people living in the state could help Democrats turn it blue.
"We see a lot of new people, a lot of influx from various parts of the country. Younger people are more moderate and things and so I think you may possibly see a blue state coming up."
Indeed, commentators have suggested that Arizona could play a key role in the 2020 election. For instance, The Wall Street Journal argued last month that the Democratic Party's "most comfortable path to victory" runs through Arizona.
The publication's columnist, William A. Galston, noted that polls suggest President Donald Trump is unlikely to win any state he did not win in 2016, pointing out that the commander-in-chief appears to be "in good shape" in states such as Florida, Ohio, and Texas.
According to Galston, Trump is in danger of losing Arizona thanks to white working-class women, who abandoned the Republican Party during the 2018 midterm elections. The president's rhetoric, which has not toned down, is thought to have driven them away from the GOP, according to the columnist, and that could happen again in 2020.